1. Field of the Invention
The present invention generally relates to the arts of speakers and more particularly to a diaphragm of a speaker.
2. Description of Related Art
In recent years, with the development of slim-type electronic devices such as liquid crystal display devices, mobile telephones, there is a demand for thin-type and slim-type speakers with high performance used in the electronic devices. Generally, such a speaker includes a diaphragm. The diaphragm is a very important element determining the performance of the speaker.
The diaphragm is typically formed from soft material by heat pressing. The soft material of the diaphragm can meet the requirement of low frequency, but at the same time affects the sound quality of high frequency. Therefore, it is difficult for a diaphragm made of single material to produce high quality sound. In order to overcome the defect mentioned above, diaphragms made of compound materials emerge because of the demand.
Generally, a compound diaphragm includes a membrane from a soft material and a dome part from a hard material overlapping the membrane.
In a related art, a compound diaphragm includes a dome part and a membrane part connected to an outer edge of the dome part. A thickness of the dome part is about 0.35 mm-0.45 mm. We need a thinner diaphragm to satisfy the demand for thin-type speakers with high performance. The thickness of the dome part determines the thickness of the whole diaphragm. A diaphragm with a dome part having an increased thickness can meet the performance requirement, however, at the same time increases the height of the speaker.
Therefore, it is necessary to provide a speaker with a diaphragm having enough thickness for meeting the requirement of performance and thin-type trend.